每N行合并单元格 LoopMergeStrategy

对每N行合并单元格 LoopMergeStrategy

对1到11列（下标从0开始） 每6行合并  

  EasyExcel.write(file)
                .head(title)
                .registerWriteHandler(new LoopMergeStrategy(6,0))
                .registerWriteHandler(new LoopMergeStrategy(6,1))
                 .registerWriteHandler(new LoopMergeStrategy(6,2))
                .registerWriteHandler(new LoopMergeStrategy(6,3))
                .registerWriteHandler(new LoopMergeStrategy(6,4))
               .registerWriteHandler(new LoopMergeStrategy(6,5))
                .registerWriteHandler(new LoopMergeStrategy(6,6))
                .registerWriteHandler(new LoopMergeStrategy(6,7))
                .registerWriteHandler(new LoopMergeStrategy(6,8))
                .registerWriteHandler(new LoopMergeStrategy(6,9))
                .registerWriteHandler(new LoopMergeStrategy(6,10))
               .sheet("市场代码+供应商明细表（月）")
                .doWrite(dataList);